1. Field of the Invention
The present invention relates to a concentrator photovoltaic unit including a lens made of resin for collecting sunlight, a photovoltaic element for generating electric power upon receiving the light collected by the resin lens, a frame-like case made of metal having openings at both end portions and a space formed therein, and a holding member for holding the photovoltaic element, and a concentrator photovoltaic apparatus in which a plurality of concentrator photovoltaic units are arranged.
2. Description of Related Art
Conventionally, a concentrator photovoltaic apparatus including a plurality of Fresnel lenses for collecting sunlight and a case used to be inclined so as to direct the plurality of Fresnel lenses toward the sun has been commercialized, and the case has a plurality of solar cells therein for respectively generating electric power upon receiving the light collected by the respective Fresnel lenses. In the concentrator photovoltaic apparatus, the plurality of Fresnel lenses are used as an upper member of the case to thereby create a space for accommodating the plurality of solar cells in the case. Further, to improve a sealing property of the space inside the case, the respective resin Fresnel lenses are bonded together with an adhesive, and the plurality of resin Fresnel lenses bonded together are fixed to an opening portion of the metal case by a fixing member, so that dust or water is prevented from entering the case (for example, see JP-A-2008-4661). As a Fresnel lens, the one having a flat or spherical shape is used therein.